Thread tensioning and withdrawing devices for bobbinchanging automatic looms



Jan. 22, 1963 A. WlRz 074,440

THREAD TENSIONING AND WITHDRAWING DEVICES FOR, BOBBIN-CHANGING AUTOMATIC LOOMS 5 Sheets-Sheet 1 Filed April 5, 1961 Null TWA-n.4.;

Jan. 22, 1963 A. wlRz THREAD TENSIDNTNG AND WITT-DRAWING DEVICES F BDBBIN-CHANGING AUTOMATIC Looms 3 Sheets-Sheet 2 Filed April s, 1961 mvsmon AuusT wfRz Flan-ALUM Jan. 22, 1963 A. wlRz 3,074,440

THREAD TENSIONING AND WITHDRAWING DEVICES FOR BOBBIN-CHANGING AUTOMATIC LOOMS Filed April Z5, 1961 3 Sheets-Sheet 3 E, LL

INVE NTOR Auusr wlRz by 7214.4.4# ATT? United States Patent 3,074,440 THREAD TENSIONING AND WITHDRAWING DE- VCES FOR BOBBIN-CI-IANGING AUTOMA'HC LOOMS August Wirz, Arbon, Thurgau, Switzerland, assigner to Adolph Saurer Ltd., Arbon, Switzerland Filed Apr. 3, 1961, Ser. No. 100,082 Claims priority, application Switzerland `luly 26, 1960 4 Claims. (Cl. 139-247) This invention relates to textile weaving, and more particularly to thread tensioning and withdrawing devices used on bobbin-changing automatic looms, and the like.

It is a primary object of this invention to provide a thread tensioning and withdrawing device particularly adapted for use in connection with the automatic bobbin changers, and particularly the vertical bobbin magazines of drop box looms, which positively controls the weft ends of a plurality of bobbins.

Another object of this invention is to provide a thread tensioning and withdrawing device of the afore-noted kind wherein the threads remain under tension until the bobbins have entered the shuttles.

It is a still further object of the invention to provide a thread tensioning and withdrawing device of the type noted above which is equally effective in withdrawing thread cuttings and the like.

Other objects, and the manner in which the same are attained, will become apparent as this specication proceeds.

The invention contemplates a support or saddle for the thread ends, mounted on the frame of the loom, at a distance from the bobbin magazine, and at least one conveyor type band or belt which during the operation of the loom, travels along such saddle or support, so as to tension and to a minor extent, Withdraw the thread ends disposed between the support and the moving belt.

In the drawing accompanying this specication and forming part thereof, an embodiment of the invention is illustrated diagrammatically by way of example.

In the drawing:

FIG. 1 is a front view, partly in section, of the upper right hand portion of a loom equipped with a thread tensioning and withdrawing mechanism according to the invention;

FIG. 2 is a plan view 0f part of the loom portion shown in FIG. l, the belt mechanism on the far right of the ligure being shown in its open, i.e. outwardly displaced position for sake of clarity;

FiGS. 3 and 4 are side views, partly in section, of details of FIG. 1 shown on a larger scale, and

FIG. 5 is a view taken in the direction of the arrow, of the mechanism illustrated in FIG. 4.

Referring to the drawing, the frame 0f the loom 1 mounts the bobbin magazine 2 which comprises conduits 3, 4, 5 and 6 accommodating the bobbins 7, 8, 9, and 10. Underneath the bobbin magazine 2, there are arranged the bobbin feeder 11 containing a bobbin 12, and the slay 13 with a shuttle 14 and a bobbin 15. The frame of the loom 1, on the right-hand side, is provided with rails 15 and 17 which mount the bearing 18 for the bobbin feeder 11, and the thread tensioning and withdrawing device according to the invention. The device 20 comprises the saddle or support 21 and the endless bands or belts 22 which are arranged for displacement, on rollers 24 and 25. The rollers 24 and 25 are mounted on the frame 30 by means of shafts 27 and 29, respectively. The saddle or support 21 is subdivided by ribs 23 into as many distinct thread supporting portions as there are passages in the bobbin magazine, i.e. four portions corresponding to passages 3, 4, 5, and 6 disposed adjacent to one another in the magazine 2. This arrangement ensures that the belts or bands 22 are well adapted to the various kinds of yarn used on the loom. Whereas the rollers 24 are rigidly mounted on the shaft 27, the rollers 25 are mounted for rotary displacement on the shaft 29. 'Ihe set-screws 32 permit varying the distance between the shafts 27 and 29 to stretch the belts 22.

'Ihe frame 30 is equipped with lugs 33 and 34 whereby it is mounted for pivotal displacement, on the shaft 35, which in turn is mounted on the rail 16. Collars 37 and 38 are lixed on the shaft 35. A spring 39 which is loosely placed around the shaft 35 tends to move the frame 30 toward the right (FIG. 5) and at the same time, to rotate it counterclockwise (FIGS. 3 and 4) so as to urge the bands or belts 22 onto the thread supporting saddle 21. The lug 34 and the collar 33 are provided with shoulders 40 and 41, respectively, which are designed to arrest the frame 30 in the outwardly displaced position shown in FIG. 2 and in dots and dashes in FIG. 3.

A spring 19 is loosely disposed 0n the shaft 35 and mounted, at one end, in the collar 38, while the other end is connected with the bell crank lever 45. 'Ihe spring 19 tends to rotate the bell crank lever 45 counterclockwise (FIG. 4). The lever 45 is provided with a pin 44 which mounts a pawl 43, and a compression spring 47, which is supported on the bell crank lever 45, urges the pawl 43 onto the ratchet wheel 42. The free end of the bell crank lever 45 is connected by the transmission member 46, e.g. a rope, with the slay 13.

As shown in FIGS. l to 3, inclusive, the ends of the threads 50, deriving from the bobbins 7, 3, 9 and 10 in the bobbin magazine 2, pass over the saddle 21, as do the ends of threads 51 and 52 deriving from the bobbins 12 and 1S which are disposed in the bobbin feeder 11 and in the shuttle 14, respectively. The same is true for the thread end 53 deriving from an unwound, empty bobbin. A guard 54 is provided to shield the thread ends hanging from the saddle 21.

In order to facilitate the disposition of the thread ends in the appropriate compartments on the saddle 21, the frame 30 can be rotated clockwise (FIG. 3), overcoming the force of the spring 39; in the course of this pivotal displacement, the spring 39 moves the frame 3? along the shaft 35 toward the right (FIG. 5), until the shoulders 40 and 41 interlock so as to arrest the frame 30 in the outwardly displaced position, shown c g. in FIG. 2. and in dots and dashes, in FIG. 3.

The device of the invention operates as follows:

The frame 30 is pivotally displaced by hand, in a clockwise direction. When the shoulders 40 and 41 are in line with one another, the force of the spring 39 moves the frame 30 along the shaft 35 toward the right until the shoulders 40 and 41 interlock so as to arrest the frame 30 in the outwardly displaced position, as shown e.g. in FIG. 2 and in dots and dashes, in FlG. 3.

The magazine 2 is filled by inserting the series of bobbins 7, 8, 9 and 10 into the passages or storage compartments 3, 4, 5 and 6, different types of yarn being assigned to correspondingly different compartments, whereupon the ends of the threads 50 are passed across the support or saddle 21. The frame 30 then is pushed manually to the left overcoming thereby the axial force of the spring 39. The rotary force of the spring 39 will displace the frame into its operative position shown e.g. in full lines in FIG. 3 so that the belts 22 come to rest on the support 21, the thread ends 50 now being clamped between the support or saddle 21 and the endless belts or bands 22. The back and forth motion of the slay 13 is transmitted, via the rope or other transmission element 45, to the bell crank lever 45 (FIG. l). The clockwise (FIG. 4) rocking motion of the bell crank lever Y tensioned until they have entered the shuttle.

45 is used to drive the thread withdrawal mechanism, by causing the pawl 43 to turn the ratchet wheel 42 xed onifthe shaft 27, andthe roller- 24 which'is also rigidly mounted on the shaft 27, in the direction of the arrow in FIG. 4, with the result that the *belt 2 2 travels in the desired direction. vThe counterclockwise vreturn movement of the bell crank lever 45 is effected by the force ofthe spring 19. During this part of the operation, the ratchet wheel 42 is prevented from turning back by the counterpawl 48 which, influenced by the spring 49', en gages the gearing of the ratchet wheel 42. Friction between the belts 22 and the thread ends causes the latter to be tensioned and to a slight extent, withdrawn from the -bobbins 7, 8, 9 and 10, so that they remain properly The thread ends deriving from the bobbin 12 in the bobbin feeder 11, and from the bobbin 15 which has just entered the shuttle 14, are tensioned in a similar fashion, while thread ends 53 from spent bobbins are withdrawn. v I wish it to be understood that I do not desire to be limited to the details of construction,fdesign,rand operation shown and described, as various modifications covered by the appended claims and involving-neither any departure from the spirit of the invention, nor any sacrice of the advantages thereof, may occur to persons skilled in the art.

I claim:

1. In a drop box loom having a frame and an automatic bobbin changer including a box type magazine mounted on said frame, a weft end tensioningland withdrawing device comprising a weft end support mounted on said frame at a distance from said magazine, atleast one endless belt arranged to travel past said support whereby to tension and withdraw the weft ends disposed between said support and said belt, spaced-rollers .mounting said belt, a'frame adapted to be pivotally displaced, mounting said rollers, and spring means larranged to oppose the pivotal displacement of said frame.

2. In a loom according to claim 1 and including a bobbin changing magazine of the type having a number of passages disposed adjacent to one another in a horizontal plane, a weft end vtensioning and withdrawing device including a weft end support, and ribs projecting' from theY surface of said support whereby to subdivide said surface into a number of compartments` corresponding to the number of said passages in the magazine.,

3. In a loom according to claim,1 and including a bobbin changing magazinef the typelalvingr a number of passagesl disposed adjacentt ton ,one-V another in a horizontal plane, a weft end tensioning and withdrawing device including an endless beltsaidl endless belt, be ing subdivided intoV a .numberof b'eltportions ,corresponding to the number of said passages yin themagaziner, i

4. In combination with a loom having a frame and f bobbin changing magazine, .mounted onsaidrfrarne, a

weft end tensioning andvwithdrawing d evice ,comprising a weft end support fixed. on said frame, ;any Aendless belt mechanism mounted f or pivotal displacement on said frame, means for urging said belt onto saidsupport, whereby to clamp the weftendsbetween the belt and the support, and means for intermittently driving said belt in synchronism with the operation of the 100m whereby to tension and withdraw said weft ends until after said` bobbins have left said magazine.

References Cited in the iile of this patent` UNITED STATES PATENTS 

1. IN A DROP BOX LOOM HAVING A FRAME AND AN AUTOMATIC BOBBIN CHANGER INCLUDING A BOX TYPE MAGAZINE MOUNTED ON SAID FRAME, A WEFT END TENSIONING AND WITHDRAWING DEVICE COMPRISING A WEFT END SUPPORT MOUNTED ON SAID FRAME AT A DISTANCE FROM SAID MAGAZINE, AT LEAST ONE ENDLESS BELT ARRANGED TO TRAVEL PAST SAID SUPPORT WHEREBY TO TENSION AND WITHDRAW THE WEFT ENDS DISPOSED BETWEEN SAID SUPPORT AND SAID BELT, SPACED ROLLERS MOUNTING SAID BELT, A FRAME ADAPTED TO BE PIVOTALLY DISPLACED, 